Thanks everybody for your patience and professionalism (sometimes forum post derail really quickly - this one went longer than I had expected). When I tried a different SGI format plugin from:  http://telegraphics.com.au/sw/product/SGIFormat  it came in like I expected (the alpha channel from the .rgba went directly into a seperate transparency alpha channel as opposed to directly (or "Alpha makes layer transparent") on the R-G-B channels). ...but I learned alot (and hopefully others benefitted as well) how the alpha/transparency works in Photoshop - and when I need to work with PNGs in the future (which I do on occasion) - the SuperPNG plugin is a great tool to make that choice. As a side note, I wonder if it would be possible to have an advanced load option on all formats that support transparency to make this choice (not sure where in the chain, and how Photoshop works under the covers, if this is even possible or worth it). ie. something like PNG (as all other formats that support transparency) would use this proposed native Photoshop capability rather than needing to get SuperPNG - and obviously all other formats would benefit/work this way. Thanks again for everyone getting me through my issue! -cheers, Steve ... View more

Noel Carboni wrote: Seems like everything that's needed to me.  Did I miss something? The issue is, if I'm trying to read an .rgba (which Photoshop is seeming to have an issue with) I don't have the benefit of a feature that can load "Alpha appear as a seperate channel" with just ANY format - only PNGs using the SuperPNG plugin. Futhermore, if I manually construct a image in Photoshop using the layer mask approach, I STILL have an additional step of moving the layer mask back out to [alpha] channel so that I can write out into .rgba properly (no format that supports transparency like.rgba or tiff,  will give you the  Save Option of "Alpha Channels"  unless the transparency is correctly placed in a true "Alpha" channel - as opposed to a Layer Mask). BTW, I have a different issue now where Photoshop CS4 won't even read my .rgba's - It seemingly writes them correctly -  once you move the transparency layer mask out to an Alpha Channel and save with PhotoShop -  I can read an .rgba with GIMP just fine.  but if I try to read this very same file into PhotoShop - Photoshop CS4 gives me a "Could not complete your request because of a program error."  Does anybody know if there is potentially a newer version of the SGI .rgba plugin than what I'm using (or some configuration I need to be aware of)? So in summary - I didn't think the format would matter for the capability I was trying to ask (unfortunately, since there was a path with SuperPNG that led us down a road that was not available to the true format that I was ultimately going to deal with - apologies - my intent was to find an example the simply demonstrated the way CS4 dealt with alpha - which I still argue isn't as flexible as it should be). I think it was still useful to have the SuperPNG to help figure out what was going on. Looks like I just need to upgrade to CS6; but unfortunately, there are still some manual steps to move around the layer mask to a true channel alpha mask just before writing.  (and potentially a bigger issue with the .rgba reader plugin). I was just surprised I have to do this much wrangling with Photoshop. ... View more

conroy, So you are on CS6? So some of the confusion in the prior posts - I ultimately will be needing to do these types of things in .rgba  -  I just used PNG as a shareable example (unfortunately I can't directly share what I'm doing). The above examples that I confused you with, was to demonstrate what I gleaned from your SuperPNG capability that is is going on with the channels without the SuperPNG plugin (or in my case, if I needed to load .rgba).  You were correct, I specifically wanted the opaque versions - I went through all that trouble (and confusion evidently) to demonstrate what I think I figured out what was going on.  Thanks for sharing the SuperPNG, I think it was key to see what I suspect is going on in CS4 of Photoshop - but I missed the the "Layer Mask From Transparency" was a CS6 capability. So the comments about not being able to edit in the RGB are when you DON'T use SuperPNG (or in my case try to load an .rgba) - I obviously didn't make it clear enough the compare and contrast of the point I was trying to make - there was a certain flowof the example (and it is getting complicated!);  apologies. conroy and Noel especially, thanks for sticking in there with me! ... View more

Noel, will the "Layer Mask From Transparency option" keep place the color channels in their "opaque" state like I require?  ...if so, you are correct about the cost/benefit.   Or I could use GIMP for free!    (I couldn't help myself Noel!)   ...but seriously I really wanted to figure out a way to stay in Photoshop to benefit from the other features where it clearly is a winner.  I am just amazed that it seemingly doesn't have a way to treat incoming files with alpha in what I consider the "correct" way - or at the very least have someway of getting it easily into that form - color and alpha channels in grayscale form that I can edit independently. I learned alot (and I hope other people benefited as well) from the journey!  ...Thanks everybody! I'd love to see if anybody has a brilliant or clever solution - but I agree with Noel - probably enough wheel-spinning on this one. ... View more

I think I've finally determined that modern Photoshops have gone in a different direction that I feel "Alpha" should be done. (good or bad). Here are the steps and/or details of how I arrived at that conclusion. If nothing else this has been very educational on how Photoshop treats alpha. - Import your alpha'd PNG with SuperPNG format (see above on how to make sure you use the SuperPNG plugin to load the .png). - In the SuperPNG dialog select "Alpha appears as seperate channel" - Create a layer from the Background and Delete the original Background   (since the Background is locked and we can't edit the Background - we want to add a layer mask based on the alpha) - Ctrl-Left Select the "Alpha 1" channel - Ctrl-C - and hit the "Add Layer Mask" button (square with the circle at the bottom of the LAYERS rollout) - For this demo and clarity, I went ahead and deleted the alpha "Alpha 1" that came in through the SuperPNG plugin So now I have the Layers like I kindof expected the main document to just come in as (kindof though - it is presented in a Layer Mask rather than Alpha Channel). What is interesting - which you'll see if you toggle the layer mask on and off (shift-click the mask thumbnail in the layer) Note how the thumbnails in the channel views render differently during the toggle. When the mask is off you see the individual color channels like I expect - black where there is an absence of that color. However when you enable the layer mask - the individual color channels show in semi-transparent/checkerboard. So this is exactly how the color channels are presented when loading in a .png (WITHOUT the SuperPNG plugin) or an .rgba ..you get the semitransparent views of the color channels - BUT the difference is - you have no way to directly see or edit the Alpha channel. nor are the color channels represented as completely opaque versions. What is really interesting - it is there though - if you Ctrl-Left Select the layer, Ctrl-C, and "Add Channel Mask" - you'll get the Alpha mask. HOWEVER, the big issue is that you can't toggle or edit the Color-Channels like the Layer counterpart above; they are ALWAYS the semitransparent/checkboard version;  AND now we basically are double applying transparency   (due to the still embedded alpha/transparency AND the newly create "Alpha 1" channel) I think this a bug (or a poor reimplementation of modern Photoshop releases; I believe older Photoshops used to break out Alpha in the "arguably correct" way - and in fact the way GIMP currently does). Or maybe there are other explanations - like abstracting some of this complexity away from less advance users, etc? So the SuperPNG plugin was useful in experimenting, understanding, and demonstrating what is going on. However, if I'm trying to read in .rgba directly, I don't think I have a way of making the "Alpha appear as a seperate channel" as I think any image with "alpha" component should. (png, tiff, rgba, etc). ... View more

R_Kelly,  (and I must thank you and everybody for their patience in this thread!) In my specific case the black in any of the four seperate channels actually means something - it means a value of 0. Visually, the following two would be result in the same exact image... transparency in the Red [grayscale] channel       -   combined with transparency from the alpha channel full black in the Red [grayscale] channel            -   combined with transparency from the alpha channel. However in my specific case they do not; AND I need to be able to edit the values in each of the 4 seperate channels. BTW, It appeared as it the Filter Factor  that Semaphoric mentioned (I assume the "Transparency" ones where what I needed) were "Currently Down!!!" so I was unable to attempt that path. http://thepluginsite.com/resources/freeff.htm ... View more

conroy,  I'm am able to load the PNG per your instructions of manually opening up the .png with the SuperPNG format.  Now I'm trying to figure if it is better to get my .rgba's through to a png with the method.  R_Kelly's method almost worked - except the color layers still have transparency in them rather than being black in the absence of that color - and more importantly, I can't seem to edit the individual channels.  (and I'm a little concerned about the 8 copies that I merge - if they will retain the exact value the original image would have if it would come in like GIMP imports the image). My goal is to have each of the channels R - G  - B - A  all be editable grayscale channels - I need to have it come in exactly because the values actually mean information (rather than just visual imagery).  ...basically how GIMP treats channels; but obviously I want to use Photoshop. ... View more

conroy, I've placed the plugin in: C:\Program Files (x86)\Adobe\Adobe Photoshop CS4\Plug-ins\SuperPNG               SuperPNG.8bi Restarted - Making sure I was running the 32bit version - since there only appears to be a 32-bit plugin. Opened a png (the one in my example). ...but I never see the dialog you mention. ... View more

Noel, Excellent - very useful information - I had always assumed the subdirectories where specific names and certain plugins needed to live. conroy,  I've placed the plugin as advised by Noel - but I still don't see an option for "Layer > Layer Mask > From Transparency" in Windows Photoshop CS4 Extended - so I assume it is a capability that is no longer exists in CS4. ...bummer, I thought we were close. Does anyone have any suggestions then how to display the R - B - B - A  data then in  seperate channels in Photoshop CS4 (as it is presented in GIMP per the example above)? ... View more

conroy,  thanks for the help!  what subdirectory, if any, underneath  Plug-ins do I place this?  The unzip content (SuperPNG\Photoshop\32-bit) doesn't indicate where I actaully place the plugin (for example, something like a file format plugin like Targa.8BI would live in Plug-ins\File Formats).  Will this capability work for my RGBA files as well? ... View more

That is what I'd like to see, but unfortunately I don't seem to have the option of "Layer > Layer Mask > From Transparency" in Windows Photoshop CS4 . ... View more